Co-reporter:Yangfan Zhang, Yunhong Tan, Kang Yang, Zexiong Wu, Zishou Zhang, Mingqiu Zhang and Kancheng Mai
Journal of Materials Chemistry A 2016 vol. 4(Issue 26) pp:10091-10097
Publication Date(Web):29 Apr 2016
DOI:10.1039/C6TA02161A
Molecular chain bonding is, for the first time, developed to synthesize a nanoporous, flexible and conductive polymer composite by converting a single polymer phase matrix to two phases of interpenetrating polymer networks. Significantly, the porous polymer composite not only presents ultra-high mechanical properties, durability and conductive stability, but also enhances the capacitance by 7-fold.
Co-reporter:Chunyan Chen;Zishou Zhang;Qian Ding;Chunguang Wang
Polymer Composites 2015 Volume 36( Issue 4) pp:635-643
Publication Date(Web):
DOI:10.1002/pc.22981
To obtain isotactic polypropylene (iPP) nanocomposites with high β-crystal content, TMB5, calcium pimelate and calcium pimelate supported on the surface of nano-CaCO3 were used as β-nucleating agent and MWCNT filled β-nucleated iPP nanocomposites were prepared. The effect of different β-nucleating agent and MWCNT on the crystallization behavior and morphology, melting characteristic and β-crystal content of β-nucleated iPP nanocomposites were investigated by DSC, XRD and POM. The results indicated that addition of MWCNT increased the crystallization temperature of iPP and MWCNT filled iPP nanocomposites mainly formed α-crystal. The β-nucleating agent can induce the formation of β-crystal in MWCNT filled iPP nanocomposites. The β-nucleating ability and β-crystal content in MWCNT filled β-nucleated iPP nanocomposites decreased with increasing MWCNT content and increased with increasing β-nucleating agent content due to the nucleation competition between MWCNT and β-nucleating agents. It is found that the calcium pimelate supported on the surface of inorganic particles as β-nucleating agent has stronger heterogeneous β-nucleation than calcium pimelate and TMB5. The MWCNT filled iPP nanocomposites with high β-crystal content can be obtained by supported β-nucleating agent. POLYM. COMPOS., 36:635–643, 2015. © 2014 Society of Plastics Engineers
Co-reporter:Mei Li, Gu Li, Juan Jiang, Zishou Zhang, Xin Dai, Kancheng Mai
Journal of Materials Science & Technology 2015 Volume 31(Issue 4) pp:331-339
Publication Date(Web):April 2015
DOI:10.1016/j.jmst.2014.11.022
ZnO is a multifunctional material with UV-blocking, antimicrobial, photo–catalytic activity and self-cleaning properties. The application of ZnO has become an interesting subject both in science and industries in the polymer materials. A great number of investigation indicated that introduction of ZnO can improve ultraviolet resistance and endow antimicrobial properties of polypropylene (PP) materials to broaden the application range and prolong the usage life of polypropylene materials. This mini-review contains examples of recent research advances on ultraviolet resistance and antimicrobial properties of ZnO in the filled polypropylene materials. It is found that ultraviolet resistance and antimicrobial properties of ZnO supported on the surface of other inorganic particles are higher than those of nano- and micro-ZnO particles, which may inspire further developments of filled PP and its copolymer materials with high ultraviolet resistance and antimicrobial properties.
Co-reporter:Mei Li;Gu Li;Zi-shou Zhang;Xin Dai;Yue-wen Yang
Chinese Journal of Polymer Science 2015 Volume 33( Issue 7) pp:976-987
Publication Date(Web):2015 July
DOI:10.1007/s10118-015-1650-y
To enhance the ultraviolet resistance of ZnO based polymer materials, ZnO-supported mesoporous zeolite (M-ZnO) was prepared and characterized by atomic absorption spectroscopy and scanning electron microscopy. The ultraviolet resistance, crystallization behavior and melting characteristics of ZnO and M-ZnO filled PPR composites were compared by FTIR spectra and differential scanning calorimetry. The ultraviolet resistance of M-ZnO filled PPR composites is higher than that of ZnO filled PPR composites, indicating higher ultraviolet resistance of M-ZnO than that of ZnO. The crystallization temperatures of mesoporous zeolite filled PPR were higher than those of M-ZnO and decreased with increasing UV-irradiation time. But the crystallization temperatures of M-ZnO filled PPR composites were not influenced by UV-irradiation time. The ZnO supported on the surface of zeolite is effective in enhancing the ultraviolet resistance of ZnO based polymer materials.
Co-reporter:Qian Ding;Zishou Zhang;Xin Dai;Mei Li
Polymer Composites 2014 Volume 35( Issue 8) pp:1445-1452
Publication Date(Web):
DOI:10.1002/pc.22797
Wollastonite-filled α-isotactic polypropylene (iPP) and β-iPP were prepared through introduction of wollastonite (W) and wollastonite with β-nucleating surface (Wx) in iPP matrix. The α- and β-nucleating ability of wollastonite, crystalline morphology, and mechanical properties of injected iPP filled by wollastonite with different nucleating surface were compared using differential scanning calorimetry, wide-angle X-ray diffraction, polarizing optical microscopy, mechanical testing, and scanning electron microscopy. The results indicated that iPP filled by wollastonite with different nucleating surface has different crystalline morphology, melting behavior, and mechanical properties. The W and Wx filled iPP mainly formed α- and β-phase iPP, respectively. The tensile and flexural modulus of iPP/W and iPP/Wx increased with increasing wollastonite content, and the tensile and flexural modulus of iPP/Wx were lower than that of iPP/W. The tensile property, flexural property, and impact strength of iPP/Wx were higher than that of iPP/W and β-iPP. The synergistic effect of reinforcing of wollastonite and toughening of β-phase leads to higher mechanical properties. POLYM. COMPOS., 35:1445–1452, 2014. © 2013 Society of Plastics Engineers
Co-reporter:Mei Li, Gu Li, Zishou Zhang, Xin Dai, Kancheng Mai
Thermochimica Acta 2014 Volume 598() pp:36-44
Publication Date(Web):20 December 2014
DOI:10.1016/j.tca.2014.11.004
•PPR were nucleated by aryl amide compounds (TMB-5), CaPA and CC100.•The non-isothermal crystallization kinetics of PPR and β-nucleated PPR was studied.•The crystallization activation energy was calculated according to Friedman method.•The nucleation activity (NE) was calculated according to Dobreva method.•We found that the nucleation efficiency is CC100 > CaPA > TMB-5.A great number of investigations demonstrated that it is more difficult for polypropylene random copolymer (PPR) to obtain high β-crystal content. To increase the β-crystallization in PPR, calcium pimelate (CaPA) supported on the surface of nano-CaCO3 (CC100) was used as a β-nucleating agent. The crystallization behavior and morphology, melting characteristics and non-isothermal crystallization kinetics of CC100 nucleated PPR were compared with PPR nucleated by aryl amide compounds (TMB-5) and CaPA by DSC, XRD and POM. The non-isothermal crystallization kinetics of PPR and β-nucleated PPR was examined by Jeziorny and Mo models. The crystallization activation energy and nucleation activity (NE) of PPR and β-nucleated PPR were calculated according to Friedman and Dobreva methods, respectively. It indicated that the β-nucleating efficiency of CC100 was higher than those of TMB-5 and CaPA. It is an effective method to enhance the β-crystallization of PPR with a supported β-nucleating agent.The Kβ values of β-nucleated PPR as a function of cooling rate (PPA, PPB and PPC represent PPR nucleated by CaPA, TMB-5 and CC100, respectively).
Co-reporter:Mei Li;Gu Li;Yifei Fan;Juan Jiang;Qian Ding;Xin Dai
Polymer Bulletin 2014 Volume 71( Issue 11) pp:2981-2997
Publication Date(Web):2014 November
DOI:10.1007/s00289-014-1236-9
To improve the photo-oxidation degradation resistance and antimicrobial ability of ZnO-filled polypropylene random copolymer (PPR), 13X zeolite particles supported with nano-ZnO with different morphologies were prepared and used to manufacture filled PPR composites. The formation of ZnO with different morphologies on the surface of 13X zeolite was proved by atomic absorption spectroscopy, scanning electron microscope, UV–vis spectra, and fluorescence spectra. The results indicated that the photo-oxidation degradation resistance of nano-ZnO-supported 13X zeolite-filled PPR composites is higher than that of PPR composites filled by the same content of pure nano-ZnO. Antimicrobial experiment results show that nano-ZnO-supported 13X zeolite-filled PPR composites exhibit higher antimicrobial properties than ZnO-filled PPR composites prepared by directly adding nano-ZnO into PPR matrix for Staphylococcus aureus and Escherichia coli. The addition of nano-ZnO-supported 13X zeolite particles increases the crystallization temperature, but has no influence on the melting behavior of PPR composites.
Co-reporter:Zishou Zhang, Teng Zhai, Xihong Lu, Minghao Yu, Yexiang Tong and Kancheng Mai
Journal of Materials Chemistry A 2013 vol. 1(Issue 3) pp:505-509
Publication Date(Web):08 Nov 2012
DOI:10.1039/C2TA00650B
A novel class of flexible carbon black and carbon nanotube filled ethylene-vinyl acetate copolymers (ExByCz) were designed and fabricated as substrates for high-performance flexible supercapacitors' electrodes. The electrodes that employed these substrates exhibited good rate capability, high specific capacitance (214.6 F g−1), high specific power density (10950 W Kg−1) and high energy density (30.4 W h Kg−1).
Co-reporter:Mei Li, Gu Li, Juan Jiang, Ye Tao, Kancheng Mai
Composites Science and Technology 2013 Volume 81() pp:30-36
Publication Date(Web):14 June 2013
DOI:10.1016/j.compscitech.2013.03.020
In order to increase the antimicrobial functionality of polypropylene random copolymer (PPR), nano-ZnO-supported on the surface of zeolite particles were prepared and used as functional fillers for PPR composites. The prepared nano-ZnO-supported zeolite particles were characterized by fluorescence and UV–Vis spectra, inductive coupled plasma and scanning electron microscopy. The crystallization behavior and crystalline morphology, antimicrobial ability and mechanical properties of zeolite, ZnO and nano-ZnO-supported zeolite filled PPR composites were investigated by differential scanning calorimeter, polarizing optical microscopy, antimicrobial and mechanical testing. The results indicated that the ZnO with flower-like morphology was formed on the surface of zeolite particles. The heterogeneous nucleation of zeolite and nano-ZnO-supported zeolite increase the crystallization temperature of PPR. The crystallization temperatures of nano-ZnO-supported zeolite filled PPR composites increase with increasing ZnO content in the nano-ZnO-supported zeolite. Incorporation of nano-ZnO-supported zeolite significantly decreases the size of spherulites of PPR. The nano-ZnO-supported zeolite filled PPR composites exhibit higher antimicrobial abilities than nano-ZnO filled PPR composite prepared by directly adding the same content of nano-ZnO into PPR matrix for the Staphylococcus aureus and Escherichia coli due to the flower-like morphology of ZnO in the nano-ZnO-supported zeolite. The nano-ZnO-supported zeolite content has little influence on the mechanical properties of PPR composites. nano-ZnO-supported zeolite as functional filler can be used to increase the antimicrobial ability of PPR.
Co-reporter:Chunguang Wang, Zishou Zhang, Qian Ding, Juan Jiang, Gu Li, Kancheng Mai
Thermochimica Acta 2013 Volume 559() pp:17-22
Publication Date(Web):10 May 2013
DOI:10.1016/j.tca.2013.02.021
In order to investigate the effect of crystallinity of second polymers on β-crystallization of β-nucleated isotactic polypropylene (β-iPP), a series of β-iPP blends with different poly(ethylene terephthalate) (PET) contents were prepared by using twin-screw extruder, and the β-iPP blends with different crystallinity PET were obtained by controlling the cooling rate, crystallization temperature and time, and melting temperature. The crystallization and melting behavior, crystalline morphology and β-crystal content have been investigated by DSC, WAXD and POM. The relationship between β-crystal content in the blends and the crystallinity of PET was discussed. Based on the effect of cooling rate, crystallization temperature and time, and melting temperature on β-crystallization of iPP in the β-iPP blend, it is considered that the crystallinity of PET is an important factor to the β-crystallization of β-iPP. The decreased crystallinity of PET would help the β-crystallization of β-iPP.Graphical abstractHighlights► PET crystallized under non-isothermal process significantly decreases β-crystallization. ► The crystallinity of PET can be controlled by different crystallization temperatures. ► The decreased crystallinity of PET is favor to increase β-crystal content.
Co-reporter:Zishou Zhang;Chunguang Wang;Yifei Du;Junping Zhang
Journal of Applied Polymer Science 2013 Volume 127( Issue 2) pp:1114-1121
Publication Date(Web):
DOI:10.1002/app.37560
Abstract
In this work, β-polypropylene/polystyrene (β-PP/PS) blends were prepared with PP, PS, and a novel supported β-nucleating agent or β-nucleated PP and PS. The β-PP/PS blends were compatabilized by PP-g-MA, PP-g-GMA, POE-g-MA, and EVA-g-MA, respectively. For exploring the effect of PS amount and compatibilizers on the β-nucleation of PP, crystallization behavior and melting characteristics, the β-crystal content and crystal morphology of β-PP are characterized by differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD), and polarized light microscopy (POM). The results indicated that the PP with high content of β-crystal was obtained by addition of CaCO3 supported β-nucleating agent (β-NA) into PP. The β-nucleation, crystallization behavior, and melting characteristics, and the β-crystal content of β-PP in these blends were not influenced by addition of PS and its amount. However, the increased content of PS decreased the size of β-spherulites of PP in these blends. The β-nucleation of PP in compatabilized blends slightly depended on the compatibilizers. β-PP/PS blends with high β-crystal content can easily be prepared. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Co-reporter:Qian Ding;Zishou Zhang;Chunguang Wang;Juan Jiang
Journal of Materials Science 2013 Volume 48( Issue 15) pp:5225-5235
Publication Date(Web):2013 August
DOI:10.1007/s10853-013-7312-y
To transform α-nucleation into β-nucleation of wollastonite surface for isotactic polypropylene (iPP), the wollastonite with a β-nucleating surface was prepared through the chemical reaction between wollastonite and pimelic acid in both liquid mixing (method A) and powder mixing (method B). The wollastonite with a β-nucleating surface was confirmed using differential scanning calorimetry (DSC), X-ray photoelectron spectroscopy analysis, wide-angle X-ray diffraction under different temperatures, thermogravimetry coupled with Fourier transform infrared spectrometry, and scanning electron microscopy. The crystallization and melting behavior and the crystalline morphology of iPP composites filled by wollastonite with a β-nucleating surface were investigated by DSC and optical microscopy. The results indicated that wollastonite filled iPP composites predominantly crystallize in the α-phase iPP and iPP composites filled by wollastonite with a β-nucleating surface mainly form β-phase iPP. It is proved that heterogeneous nucleating mechanism has been changed from α-nucleation into β-nucleation of wollastonite surface for iPP crystallization. What deserves to be mentioned is that the nucleation density of flat surface in the end of needle-like wollastonite is higher than that of curved surface of wollastonite.
Co-reporter:Qian Ding;Zishou Zhang;Chunguang Wang;Juan Jiang;Gu Li
Polymer Bulletin 2013 Volume 70( Issue 3) pp:919-938
Publication Date(Web):2013 March
DOI:10.1007/s00289-012-0896-6
Wollastonite (W) with β-nucleating effect (β-W100) for iPP crystallization was obtained through reaction between Ca2+ in wollastonite and pimelic acid (PA) and the β-iPP composites filled by different content of β-W100 were prepared. The effect of PA and wollastonite contents on β-nucleation, crystallization and melting behavior, and crystalline morphology of W and β-W100-filled iPP composites was investigated by differential scanning calorimetry (DSC), wide-angle X-ray diffraction, and polarizing optical microscopy. The results indicated that incorporation of W and β-W100 increase the crystallization peak temperature of iPP due to its heterogeneous nucleating ability. And iPP/W composites predominantly crystallize in the α-phase iPP and iPP/β-W100 composites in the β-phase iPP. The results of DSC multi-scanning in same and different melting temperatures showed that β-W100 not only has strong heterogeneous β-nucleating effect but also DSC multi-scanning in same and different melting temperatures has no influence on the heterogeneous β-nucleating effect of β-W100. The β-iPP containing high wollastonite content with high β-phase content can be easily prepared.
Co-reporter:Juan Jiang, Gu Li, Hao Liu, Qian Ding, Kancheng Mai
Composites Part A: Applied Science and Manufacturing 2013 Volume 45() pp:88-94
Publication Date(Web):February 2013
DOI:10.1016/j.compositesa.2012.10.002
In order to prepare the zeolite filled β-iPP composites, zeolite supported by calcium pimelate as β-nucleator (β-zeolite) was prepared by the interaction between calcified zeolite and pimelic acid. The effects of Ca(Ac)2 solution concentration in the prepared calcified zeolite process and pimelic acid content on β-nucleating ability of β-zeolite were investigated and the crystallization and melting characteristic of zeolite, calcified zeolite and β-zeolite filled iPP composites were compared. DSC and WXAD analysis indicated that the zeolite and calcified zeolite have α-nucleation and the prepared β-zeolite has high β-nucleating ability for iPP crystallization. The β-nucleating ability of prepared β-zeolite is dependent of Ca(Ac)2 solution concentration and pimelic acid content. The prepared β-zeolite content has little influence on the crystallization and melting characteristic and the β-phase content of the filled iPP composites. The zeolite filled β-iPP composites with high β-phase content can be easily obtained by adding β-zeolite into the iPP matrix.
Co-reporter:Juan Jiang, Gu Li, Qian Ding, Kancheng Mai
Polymer Degradation and Stability 2012 Volume 97(Issue 6) pp:833-838
Publication Date(Web):June 2012
DOI:10.1016/j.polymdegradstab.2012.03.046
In order to increase the antimicrobial properties and ultraviolet resistance of isotactic polypropylene (iPP), ZnO-supported zeolite particles were prepared and used as multifunctional filler for iPP composites. The ZnO-supported zeolites with different ZnO contents were obtained by treating the mixture of zeolite and zinc acetate by different methods. Atomic absorption spectroscopy, scanning electron microscope and wide-angle X-ray diffraction experiment indicated that the ZnO was formed on the surface of zeolite particles. UV-irradiation results showed that the ultraviolet resistance of ZnO-supported zeolite filled iPP composites is higher than that of iPP composite filled by the same content of micro ZnO. The ZnO-supported zeolite filed iPP composites exhibit higher antimicrobial abilities than ZnO filled iPP composites prepared by directly adding micro ZnO into iPP matrix for the Staphylococcus aureus and Escherichia coli. Incorporation of ZnO and zeolite increases the crystallization temperatures of iPP due to the heterogeneous nucleation of ZnO and zeolite particles. The prepared ZnO-supported zeolite particles have no influence on the crystallization and melting behavior of zeolite filled iPP composites. The ZnO-supported zeolite particles are an effective filler to prepare iPP composites with antimicrobial ability and ultraviolet resistance.
Co-reporter:Zishou Zhang;Chunguang Wang;Zhang Junping
Polymer International 2012 Volume 61( Issue 5) pp:818-824
Publication Date(Web):
DOI:10.1002/pi.4148
Abstract
To investigate the nucleation of metal pimelate for isotactic polypropylene (iPP) crystallization, iPP filled with a series of metal oxides with and without metal pimelate on their surface was prepared. There was a chemical reaction between pimelic acid (PA) and metal oxides MgO, CaO, BaO or ZnO, but not TiO2. The corresponding metal pimelate formed by the chemical reaction between PA and MgO, CaO, BaO or ZnO had a different influence on the crystallization behavior and melting characteristics of iPP. Addition of metal oxides increased the crystallization temperature of iPP and mainly formed α-phase due to the heterogeneous α-nucleation of metal oxides. The α-nucleation of CaO could be easily changed into β-nucleation using CaO-supported PA, and 90.1% β-phase was obtained. The β-nucleation of BaO could be markedly enhanced by barium pimelate formed using supported PA. However, no β-phase was observed for iPP filled with MgO- or ZnO-supported PA. The various metal oxides with supported PA had a different influence on the crystallization behavior and melting characteristics of iPP due to the different structure of metal pimelate formed by chemical reaction between PA and the metal oxides. Copyright © 2012 Society of Chemical Industry
Co-reporter:Qian Ding, Zishou Zhang, Chunguang Wang, Juan Jiang, Gu Li, Kancheng Mai
Thermochimica Acta 2012 Volume 536() pp:47-54
Publication Date(Web):20 May 2012
DOI:10.1016/j.tca.2012.02.023
In order to obtain wollastonite filled β-iPP composites, wollastonite treated with pimelic acid (W*) were prepared with various mass ratios of wollastonite/pimelic acid (W/PA). The crystallization behavior, melting characteristics and β-nucleating ability of iPP composites filled with wollastonite (W) and W* were investigated by DSC and XRD. The results indicated that addition of wollastonite increased the crystallization temperatures of iPP, but the crystallization temperatures of iPP in iPP/W* composites were higher than those of iPP/W composites, which proved that the β-nucleation of W* is stronger than untreated wollastonite. Although iPP/wollastonite composites mainly form α-phase iPP, modification of wollastonite by PA significantly enhanced nucleation of β-phase iPP. The β-nucleating ability of W* depend on the amount of formed calcium pimelate, therefore the β-phase contents of β-iPP/W* composites increased with increasing W* content and decreasing mass ratio of W/PA. Moreover, there exist different critical mass ratios of W/PA for preparation of β-iPP composites filled with different W* contents with highest β-phase content and low cost.Highlights► High β-phase content iPP composites with low cost and easy process were prepared. ► The β-nucleation of wollastonite was enhanced significantly through reaction. ► Mass ratios of wollastonite/pimelic acid on iPP crystallization were investigated. ► Increasing the content of treated wollastonite will increase β-phase content.
Co-reporter:Juan Jiang, Gu Li, Nanshu Tan, Qian Ding, Kancheng Mai
Thermochimica Acta 2012 Volume 546() pp:127-133
Publication Date(Web):20 October 2012
DOI:10.1016/j.tca.2012.07.032
In order to prepare the zeolite filled β-iPP composites, the calcium pimelate as β-nucleator supported on the surface of zeolite (β-zeolite) was prepared by the interaction between calcified zeolite and pimelic acid. The β-nucleation, crystallization behavior and melting characteristic of zeolite, calcified zeolite and β-zeolite filled iPP composites were investigated by differential scanning calorimetry and wide-angle X-ray diffractometer. The results indicated that addition of the zeolite and calcified zeolite as well as β-zeolite increased the crystallization temperature of iPP. The zeolite and calcified zeolite filled iPP composites mainly crystallized in the α-crystal form and the strong β-heterogeneous nucleation of β-zeolite results in the formation of only β-crystal in β-zeolite filled iPP composites. The zeolite filled β-iPP composites with high β-crystal contents (above 0.90) can be easily obtained by adding β-zeolite into iPP matrix.Graphical abstractHighlights► The supported calcium pimelate β-zeolite was prepared. ► The β-nucleation of zeolite was enhanced dramatically through reaction. ► High β-phase content iPP composites were obtained by introducing the β-zeolite into iPP.
Co-reporter:Chunguang Wang;Zishou Zhang;Yifei Du;Junping Zhang
Polymer Bulletin 2012 Volume 69( Issue 7) pp:847-859
Publication Date(Web):2012 October
DOI:10.1007/s00289-012-0804-0
β-PP/acrylonitrile–butadiene–styrene (ABS) blends were prepared with PP, ABS and a novel supported β-nucleating agent or β-PP and ABS. The effect of ABS on the β-nucleation of PP and crystallization and melting behavior of β-PP/ABS blends were investigated by differential scanning calorimeter, wide angle X-ray diffraction, and polarized light microscopy. Results suggested that addition of low content of ABS has no effect on the β-nucleation of PP and crystallization behavior, and melting characteristic of β-PP/ABS blends. However, the increasing content of ABS decreases the β-nucleation, crystallization temperatures, and spherulite size of PP in the blends. However, the blends with the β-PP content above 80 % were obtained at the content of ABS below 40 %.
Co-reporter:Zishou Zhang, Chunguang Wang, Yuezhong Meng, Kancheng Mai
Composites Part A: Applied Science and Manufacturing 2012 Volume 43(Issue 1) pp:189-197
Publication Date(Web):January 2012
DOI:10.1016/j.compositesa.2011.10.008
High performance β-polypropylene (β-PP) nanocomposites were prepared by nano-CaCO3 with β-nucleation (β-CC) filled PP, and the crystallization and mechanical properties of β-PP nanocomposites were investigated. The results show that β-CC prepared by nano-CaCO3 supported β-nucleating agent calcium pimelate (CaPA) does not only increase the crystallization temperature of PP, but also induce the forming of a number of β-PP. It indicates that the nucleation mechanism of nano-CaCO3 has been changed from α- to β-nucleation. The notched impact strength of β-CC filled PP nanocomposites was higher than that of CC filled PP and CaPA nucleated PP. It is suggested that there is a synergistic effect of toughening of CC and toughness of β-PP. Meanwhile, the reinforcing of CC nanoparticles increased the stiffness of β-PP. The synergistic toughening effect of CC and β-PP was discussed. This method can be extended to prepare other high performance filled β-PP composites.
Co-reporter:Chunguang Wang, Zishou Zhang, Yifei Du, Junping Zhang, Kancheng Mai
Thermochimica Acta 2011 Volume 524(1–2) pp:157-164
Publication Date(Web):20 September 2011
DOI:10.1016/j.tca.2011.07.008
β-Polypropylene/poly (styrene-co-acrylonitrile) blends (β-PP/AS) were prepared with PP, a novel supported β-nucleating agent (β-NA) and AS (method one) or β-nucleated PP and AS (method two). The influence of AS on the β-nucleation for β-nucleated PP has been analyzed. The results indicated that PP with high content of β-crystal was obtained by adding β-NA into PP. The DSC studies showed that AS and its content had little effect on crystallization and melting characteristics of β-nucleated PP, and the content of β-crystal calculated from WAXD is higher than 0.94 in all blends. β-PP/AS blends with high content of β-crystal were obtained easily. AS dispersed mainly into β-spherulite of PP as small spherular particles, and the integrity of β-spherulite decreases gradually with the increase of AS content. The etched experiment also proved that β-NA dispersed in the AS phase or interface between PP and AS.Highlights► The β-PP/AS blends with high β-crystal content can easily be prepared by mixing PP, AS and β-NA or β-PP and AS. ► Addition of AS reduced slightly the crystallization temperature and the content of β-crystal of PP. ► It is proved by the POM and the etched experiment that β-NA mostly disperses in AS phase or interface between PP and AS. ► Increasing the content of AS resulted in the formation of β-PP spherulites with less perfection.
Co-reporter:Zhugen Yang
Journal of Applied Polymer Science 2011 Volume 119( Issue 6) pp:3566-3573
Publication Date(Web):
DOI:10.1002/app.33040
Abstract
A highly novel nano-CaCO3 supported β-nucleating agent was employed to prepare β-nucleated isotactic polypropylene (iPP) blend with polyamide (PA) 66, β-nucleated iPP/PA66 blend, as well as its compatibilized version with maleic anhydride grafted PP (PP-g-MA), maleic anhydride grafted polyethylene-octene (POE-g-MA), and polyethylene-vinyl acetate (EVA-g-MA), respectively. Nonisothermal crystallization behavior and melting characteristics of β-nucleated iPP and its blends were investigated by differential scanning calorimeter and wide angle X-ray diffraction. Experimental results indicated that the crystallization temperature (T) of PP shifts to high temperature in the non-nucleated PP/PA66 blends because of the α-nucleating effect of PA66. T of PP and the β-crystal content (Kβ) in β-nucleated iPP/PA66 blends not only depended on the PA66 content, but also on the compatibilizer type. Addition of PP-g-MA and POE-g-MA into β-nucleated iPP/PA66 blends increased the β-crystal content; however, EVA-g-MA is not benefit for the formation of β-crystal in the compatibilized β-nucleated iPP/PA66 blend. It can be relative to the different interfacial interactions between PP and compatibilizers. The nonisothermal crystallization kinetics of PP in the blends was evaluated by Mo's method. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Co-reporter:Ming Lu, Xiang Zhao, Lan Chen, Xiaomin Xiong, Jingxiu Zhang, Kancheng Mai, Chuanbin Wu
Polymer 2011 Volume 52(Issue 4) pp:1102-1106
Publication Date(Web):17 February 2011
DOI:10.1016/j.polymer.2010.11.053
The main purpose of this study is to examine the effect of nucleation on the formation of polymorphism in melt-crystallized syndiotactic polystyrene (sPS). By depressing the nucleation barrier (i.e., introducing nucleating agent), the tendency of forming, a metastable crystalline phase, α crystal, significantly increased. The metastability of crystalline phase was dependent upon the nucleation process in which the lower nucleation barrier led to the formation of metastable phase. Consistently, by crystallizing under shearing, the formation of α crystal dominated the crystalline polymorphism. Herein we suggest a practical method to control the polymorphism of melt-crystallized sPS.
Co-reporter:Zishou Zhang;Chunyan Chen;Chunguang Wang;Zhang Junping
Polymer International 2010 Volume 59( Issue 9) pp:1199-1204
Publication Date(Web):
DOI:10.1002/pi.2847
Abstract
In order to increase the isotactic content of β-nucleated polypropylene (β-iPP) and decrease the cost of its production, the investigation and development of novel highly efficient β-nucleators are important issues. Nano-CaCO3 was used as a support to prepare a supported β-nucleator, nano-CaCO3-supported calcium pimelate. Fourier transform infrared spectral analysis shows that an in situ chemical reaction takes place between nano-CaCO3 and pimelic acid. Differential scanning calorimetry results indicate that the crystallization and melting temperatures of β-phase in supported β-nucleator-nucleated iPP are higher than those of calcium pimelate-nucleated iPP. The β-nucleating ability of the supported β-nucleator is little influenced by the cooling rate and crystallization temperature over a wide range. The decreased content of pimelic acid in the supported β-nucleator slightly decreases the crystallization temperature of iPP but it has no influence on the content of β-phase in nucleated iPP. A novel supported β-nucleator has been successfully synthesized via pimelic acid supported on the surface of CaCO3. The crystallization temperature of iPP and melting temperature of β-phase in iPP nucleated using the supported β-nucleator are higher than those of iPP nucleated using calcium pimelate. The concept of a supported nucleator will provide a new way to increase the efficiency of polymer additives and to decrease the amounts of them that need to be used by using nanoparticles as supports. Copyright © 2010 Society of Chemical Industry
Co-reporter:Zhugen Yang, Kancheng Mai
Thermochimica Acta 2010 Volume 511(1–2) pp:152-158
Publication Date(Web):20 November 2010
DOI:10.1016/j.tca.2010.08.007
β-Nucleated isotactic polypropylene (β-iPP) blend with maleic anhydride grafted polyethylene-vinyl acetate (EVA-g-MA) and β-iPP/polyamide (PA) 6 blend, as well as its compatibilized version with EVA-g-MA as a compatibilizer were prepared with an internal mixer. Analysis from differential scanning calorimeter (DSC) and wide angle X-ray diffraction (WAXD) indicates that the addition of EVA-g-MA into β-nucleated iPP decreases the crystallization temperature (Tcp) of PP, but it has no pronounced influence on the β-crystal content for β-nucleated iPP. For β-nucleated iPP/PA6 blends, PA6 obviously decreases the β-crystal content. However, the addition of EVA-g-MA is quite benefit for the formation of β-crystal in β-nucleated iPP/PA6 blends and the β-crystal content increases with increasing EVA-g-MA content. It is suggested that the nucleating agent mainly disperses in the PA6 phase and/or the interface between iPP and PA6 in iPP/PA6 blend, which was proved by etching the blends with sulfuric acid and experimental facts from SEM.
Co-reporter:Yuhai Wang;Hao Shen;Gu Li
Journal of Thermal Analysis and Calorimetry 2010 Volume 99( Issue 2) pp:399-407
Publication Date(Web):2010 February
DOI:10.1007/s10973-009-0130-4
The effect of different interfacial interaction on the crystallization and melting behavior of PP/nano-CaCO3 composites was investigated using differential scanning calorimetry, X-ray diffraction and polarized optical microscope. The results indicated that nano-CaCO3 acted as heterogeneous nuclei for PP crystallization. There existed a synergistic effect of heterogeneous nucleation between nano-CaCO3 and compatibilizer for PP crystallization, which was proved by increasing the crystallization rate and decreasing the fold surface free energy as well as favoring the formation of β-crystal of PP. However, this synergistic effect was dependent on the interfacial interaction between PP and compatibilizer. The increased miscibility between compatibilizer and PP favored this synergistic effect.
Co-reporter:Zhugen Yang;Chunyan Chen;Dianwei Liang;Zishou Zhang
Polymer International 2009 Volume 58( Issue 12) pp:1366-1372
Publication Date(Web):
DOI:10.1002/pi.2671
Abstract
BACKGROUND: The distribution of nucleating agents in different phases is still an open question in general, and how to control conditions to prepare alloys rich in β-crystals of polypropylene (PP) is hardly reported. The main goal of this study was to find out the factors influencing the β-crystal content in β-nucleated PP/polyamide 6 (PA6) alloys and determine the best preparation conditions to obtain β-nucleated PP/PA6 alloys rich in β-crystals.
RESULTS: The compounding methods had little influence on the crystallization temperature of both PP and PA6. However, the melting characteristic and β-crystal content in β-nucleated PP/PA6 alloys not only depended upon the compounding methods, but also on the temperature at which the nucleating agent was added. A higher β-crystal content can be obtained by adding the nucleating agent at a temperature below 190 °C, which is also dependent on the mixing time.
CONCLUSION: It is proved by etching the alloys with sulfuric acid that the nucleating agent mainly disperses in the PA6 phase and/or the interface between PP and PA6 when blended at high temperature. Copyright © 2009 Society of Chemical Industry
Co-reporter:Yuhai Wang;Hao Shen;Gu Li
Journal of Applied Polymer Science 2009 Volume 113( Issue 3) pp:1584-1592
Publication Date(Web):
DOI:10.1002/app.30057
Abstract
To investigate the effect of interfacial interaction on the crystallization and mechanical properties of polypropylene (PP)/nano-CaCO3 composites, three kinds of compatibilizers [PP grafted with maleic anhydride (PP-g-MA), ethylene–octene copolymer grafted with MA (POE-g-MA), and ethylene–vinyl acetate copolymer grafted with MA (EVA-g-MA)] with the same polar groups (MA) but different backbones were used as compatibilizers to obtain various interfacial interactions among nano-CaCO3, compatibilizer, and PP. The results indicated that compatibilizers encapsulated nano-CaCO3 particles, forming a core–shell structure, and two interfaces were obtained in the compatibilized composites: interface between PP and compatibilizer and interface between compatibilizer and nano-CaCO3 particles. The crystallization and mechanical properties of PP/nano-CaCO3 composites were dependent on the interfacial interactions of these two interfaces, especially the interfacial interaction between PP and compatibilizer. The good compatibility between PP chain in PP-g-MA and PP matrix improved the dispersion of nano-CaCO3 particles, favored the nucleation effect of nano-CaCO3, increased the tensile strength and modulus, but reduced the ductility and impact strength of composites. The partial compatibility between POE in POE-g-MA and PP matrix had little effect on crystallization and mechanical properties of PP/nano-CaCO3 composites. The poor compatibility between EVA in EVA-g-MA and PP matrix retarded the nucleation effect of nano-CaCO3, and reduced the tensile strength, modulus, and impact strength. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Co-reporter:Zhugen Yang;Zishou Zhang;Youji Tao
Journal of Applied Polymer Science 2009 Volume 112( Issue 1) pp:1-8
Publication Date(Web):
DOI:10.1002/app.29362
Abstract
β-Nucleated isotactic polypropylene (iPP) blends with polyamide 6 (PA6) were prepared with a novel and highly efficient nano-CaCO3-supported β-nucleating agent. Maleic anhydride grafted polypropylene (PP-g-MA), glycidyl methacrylate grafted polypropylene (PP-g-GMA), maleic anhydride grafted poly(ethylene octene) (POE-g-MA), and maleic anhydride grafted poly(ethylene vinyl acetate) (EVA-g-MA) elastomers were added to the blends as compatibilizers. The nonisothermal crystallization behavior and melting characteristics of β-nucleated iPP and its blends were investigated with differential scanning calorimetry and wide-angle X-ray diffraction. The results indicated that the β-iPP content in the β-nucleated iPP blends depended not only on the preparation conditions but also on the compatibilizer type. A high β-iPP content (>95%) in the β-nucleated iPP/PA6 blends was obtained. The addition of PP-g-MA, POE-g-MA, and EVA-g-MA to the β-nucleated iPP/PA6 blends increased the content of β-iPP but decreased the crystallization temperature of iPP in the β-nucleated iPP/PA6 blends. However, the addition of PP-g-GMA decreased the content of β-iPP in the β-nucleated iPP/PA6 blends. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Co-reporter:Hao Shen, Yuhai Wang, Kancheng Mai
Thermochimica Acta 2009 Volume 483(1–2) pp:36-40
Publication Date(Web):10 February 2009
DOI:10.1016/j.tca.2008.10.025
Effect of different compatibilizers and magnesium hydroxide (MH) on morphology, thermal stability and mechanical properties of polypropylene (PP) composites were investigated in this study. Two different types of compatibilizers namely, polypropylene grafted-maleic anhydride (PP-g-MA) and ethylene–octene copolymer grafted-maleic anhydride (POE-g-MA) were used in this study. The results indicated that the degradation of PP/MH composites contained two steps: decomposition of MH and degradation of macromolecular. MH particles acting as physical barrier improved the thermal stability of PP, especially in oxygen. POE-g-MA enhanced it furthermore. Introduction of PP-g-MA or POE-g-MA to PP/MH composites resulted in considerable improvement in mechanical properties. The addition of PP-g-MA was most effective in increasing the tensile strength, while addition of POE-g-MA greatly increased the impact strength of PP/MH composites.Morphological investigation revealed that the improvement was attributed to the formation of encapsulation structure in these compatibilized PP/MH composites.
Co-reporter:Xin Chen
Journal of Applied Polymer Science 2008 Volume 110( Issue 6) pp:3401-3409
Publication Date(Web):
DOI:10.1002/app.28452
Abstract
The crystalline morphology and dynamical crystallization of antibacterial polypropylene composite and pure polypropylene were investigated via differential scanning calorimeter (DSC), wide angle X-ray diffraction (WAXD), and real-time hot-stage optical microscopy (OM). The results reveal that the crystalline morphology of antibacterial PP composites changes with variations of the crystallization conditions and compositions. The crystalline phase consists of both α-PP and β-PP crystals. The content of β-PP decreases with the increase in antibacterial agent content and cooling rate. With the addition of β-nucleating agent, the morphologies of all dynamically crystallized antibacterial PP composites show no obvious spherulitic morphology, and the decrease of crystal perfection and the increase of nucleation density of antibacterial PP composite system could be observed. With the increase of antibacterial agent content, the overall crystallization rates of the antibacterial PP composite increase dramatically, while the content of β-PP in all antibacterial PP composite decrease distinctly under given cooling conditions. These results can be explained by the interruptive effect of antibacterial agent on interactions of β-nucleating agent components and the obstructing effect of antibacterial agent on the mobility of PP chains in melts. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Co-reporter:Hao Shen, Yuhai Wang, Kancheng Mai
Thermochimica Acta 2007 Volume 457(1–2) pp:27-34
Publication Date(Web):15 June 2007
DOI:10.1016/j.tca.2007.02.023
Polypropylene (PP) blends with three kinds of grafted macromolecules, PP/Mg(OH)2 composites and its composites modified by different compatibilizers were prepared by melt extrusion in a twin screw extruder. The crystallization and melting behaviors of PP blends and PP/Mg(OH)2 composites were investigated with differential scanning calorimeter (DSC). The results indicated that addition of PP-g-MA has no influence on the crystallization temperature of PP, but POE-g-MA and EVA-g-MA decrease the crystallization temperature of PP. For PP/Mg(OH)2 composites, addition of Mg(OH)2 increases the crystallization temperature of PP and induces the formation of β-crystal in PP matrix. For PP/Mg(OH)2 composites modified by different compatibilizers, the synergism effect of heterogeneous nucleation of Mg(OH)2 and PP-g-MA or POE-g-MA further increases the crystallization temperatures. For PP/Mg(OH)2 composites modified by EVA-g-MA, the addition of EVA-g-MA to PP/Mg(OH)2 composite has little effect on the crystallization and melting behavior of PP. It is suggested the synergism effect of heterogeneous nucleation of Mg(OH)2 and compatibilizer depends upon the compatibilization between PP and compatibilizer. The increase in crystallization temperatures of PP in PP/Mg(OH)2/compatibilizer facilitates the formation of α-PP, but weakens the formation of β-PP.
Co-reporter:Zhidan Lin;Chunlian Zeng
Frontiers of Chemical Science and Engineering 2007 Volume 1( Issue 1) pp:81-86
Publication Date(Web):2007 February
DOI:10.1007/s11705-007-0017-5
The multiple melting-peak behavior of polypropylene (PP) in nano-CaCO3/PP composites and modified nano-CaCO3/PP composites were investigated under the condition of isothermal crystallization and nonisothermal crystallization. The result indicated that the addition of nano-CaCO3 markedly increased the crystallization temperatures of PP and induced the formation of the β-crystal of PP. The crystallization temperatures of nano-CaCO3/PP composites modified by reactive monomers were further increased, but the melting-peak intensity of the β-crystal of PP was not greatly influenced. While in the presence of dicumyl peroxide, nano-CaCO3/PP composites modified by reactive monomers led to the significant increase in the melting-peak intensity of the β-crystal of PP. The double melting-peak of PP was observed, which was attributed to the formation of two kinds of different crystallization forms of α-crystal or β-crystal during the crystallization of PP. With the increase of crystallization temperatures, the double melting-peak moved toward the high-temperature side. The intensity of high-temperature melting peak was higher than that of low-temperature melting peak in nano-CaCO3/PP composites. While in modified nano-CaCO3/PP composites crystallized at higher temperature, the intensity of high-temperature melting peak was lower than that of low-temperature melting peak. The isothermal crystallization time had little effect on the melting temperatures.
Co-reporter:Zishou Zhang, Teng Zhai, Xihong Lu, Minghao Yu, Yexiang Tong and Kancheng Mai
Journal of Materials Chemistry A 2013 - vol. 1(Issue 3) pp:NaN509-509
Publication Date(Web):2012/11/08
DOI:10.1039/C2TA00650B
A novel class of flexible carbon black and carbon nanotube filled ethylene-vinyl acetate copolymers (ExByCz) were designed and fabricated as substrates for high-performance flexible supercapacitors' electrodes. The electrodes that employed these substrates exhibited good rate capability, high specific capacitance (214.6 F g−1), high specific power density (10950 W Kg−1) and high energy density (30.4 W h Kg−1).
Co-reporter:Yangfan Zhang, Yunhong Tan, Kang Yang, Zexiong Wu, Zishou Zhang, Mingqiu Zhang and Kancheng Mai
Journal of Materials Chemistry A 2016 - vol. 4(Issue 26) pp:NaN10097-10097
Publication Date(Web):2016/04/29
DOI:10.1039/C6TA02161A
Molecular chain bonding is, for the first time, developed to synthesize a nanoporous, flexible and conductive polymer composite by converting a single polymer phase matrix to two phases of interpenetrating polymer networks. Significantly, the porous polymer composite not only presents ultra-high mechanical properties, durability and conductive stability, but also enhances the capacitance by 7-fold.
